Kata

Factorials are often used in probability and are used as an introductory problem for looping constructs. In this kata you will be summing together multiple factorials.

Here are a few examples of factorials:

4 Factorial = 4! = 4 * 3 * 2 * 1 = 24

6 Factorial = 6! = 6 * 5 * 4 * 3 * 2 * 1 = 720

In this kata you will be given a list of values that you must first find the factorial, and then return their sum.

For example if you are passed the list [4, 6] the equivalent mathematical expression would be 4! + 6! which would equal 744.

Good Luck!

Note: Assume that all values in the list are positive integer values > 0 and each value in the list is unique.

Also, you must write your own implementation of factorial, as you cannot use the built-in math.factorial() method.